Humans have intensively sailed the Mediterranean and European Atlantic waters throughout history, from the upper Paleolithic until today and centuries of human seafaring have established complex coastal and cross-seas navigation networks. Historical literature revealed three major long-lasting maritime routes (eastern, western, northern) with four commencing locations (Alexandria, Venice, Genoa, Gibraltar) and a fourth route (circum-Italian) that connected between them. Due to oceangoing and technological constraints, most voyages were coastal, lasted weeks to months, with extended resting periods, allowing the development of fouling organisms on ship hulls. One of the abiding travellers in maritime routes is the colonial ascidian Botryllus schlosseri already known since the eighteenth century in European and Mediterranean ports. This species, was almost certainly one of the common hull fouling travellers in all trade routes for centuries. Employing COI haplotypes (1008 samples) and microsatellite alleles (995 samples) on colonies sampled from 64 pan-European sites, present-day Botryllus populations in the Mediterranean Sea/European Atlantic revealed significant segregation between all four maritime routes with a conspicuous partition of the northern route. These results reveal that past anthropogenic transports of sedentary marine species throughout millennia long seafaring have left their footprint on contemporary seascape genetics of marine organisms.

从旧石器时代晚期一直到今天，人类在地中海和欧洲大西洋水域频繁航行，几个世纪的人类航海已经建立了复杂的沿海和跨海导航网络。历史文献揭示了三大持久的海上路线（东方、西方、北方），有四个起始地点（亚历山大、威尼斯、热那亚、直布罗陀）和连接它们的第四条路线（环意大利）。由于远洋航行和技术限制，大多数航行都是沿海航行，持续数周至数月，休息时间较长，导致船体上污垢生物的生长。海上航线上常驻的旅行者之一是殖民地海鞘Botryllus schlosseri，自十八世纪以来就在欧洲和地中海港口中广为人知。几乎可以肯定，这个物种是几个世纪以来所有贸易路线上最常见的船体污染旅行者之一。对从 64 个泛欧地点采样的菌落采用COI单倍型（1008 个样本）和微卫星等位基因（995 个样本），当今地中海/欧洲大西洋的灰霉属种群显示出所有 4 条海上路线之间存在显着的隔离，其中明显的分区北线。这些结果表明，过去数千年的航海过程中定居海洋物种的人为运输在当代海洋生物的海景遗传学中留下了足迹。